WO2002091487A1 - Light emitting apparatus - Google Patents

Abstract

A high-practicality light emitting apparatus which realizes a white LED high in color rendering performance, and uses a rare-earth complex more widely as a high-efficiency wavelength conversion light emitting device, wherein a rare-earth element, especially a specific complex centered around Eu (europium) ion is carried on a transparent solid carrier such as polymer and plastics, and the rare-earth /complex is excited by an InGaN blue light emitting diode or semiconductor laser using the diode luminous layer to thereby produce a complex light emitting apparatus. A combination of the blue light emitting diode, a YAG yellow phosphor and the red light of the Eu complex gives a high-color-rendering white light source. A combination of the semiconductor laser and plastics containing the complex can be widely used for automobile parts as a light-weight/compact and long-life luminous element.

Description

Technical field

 The present invention relates to a light emitting device in which a wavelength conversion material containing an organic phosphor composed of a rare earth complex is combined with a light emitting diode or a semiconductor laser that excites the wavelength converting material. Light

Background art

 One of the features of light emitting diodes (LEDs) is that they are highly monochromatic (ie, have a narrow spectral bandwidth at half maximum). Utilizing this special feature, full-color display devices in which red (R) green (G) blue (B) color LED emitters are mounted vertically and horizontally on a plane are already widely used. In this case, the display color is arbitrarily controlled by the intensity ratio of each RGB color.

 However, LEDs still have many problems when viewed as lighting devices rather than as display devices. As described above, white light can be obtained by using a device in which RGB LED light emitters are arranged and setting the intensity ratio of each RGB color appropriately, but when viewed as a lighting device, a conventional lighting device Compared with the incandescent lamps and fluorescent lamps, there are problems such as (1) the scale of the device is large, (2) the RGB colors must be controlled independently, and (3) the "color rendering properties" are poor.

Here, “color rendering” refers to the nature of the light source, such as what color the object looks like when the object is illuminated by the light source. In light of the importance of color rendering in lighting systems, the CIE (Commissions Internationale Il e de l'Eclairage, International Commission on Illumination) established a method for evaluating color rendering in 1964. According to this, a series of reference light sources that can be selected according to the color temperature of the light source to be evaluated is determined, and the color rendering index Ra is calculated from the color shift when the test light source illuminates the test light with the reference light source and the light source to be evaluated. Are stipulated. The color rendering index Ra takes a value of 0 to 100. When the color rendering index is 100, the light source to be evaluated matches the reference light source in terms of color appearance. As a reference light source, a perfect radiator is used for color temperatures of 5000K or lower, and a calculated value of the spectral distribution of daylight (referred to as synthetic daylight) is used for a temperature exceeding 5000K. You. As test colors, eight colors having a predetermined spectral reflectance are selected for general use, and the color rendering index calculated by this is called an average color rendering index. In addition, seven colors have been selected for special purposes, including the Japanese skin color. The color rendering index calculated in this way is called a special color rendering index. For more details, see “Lighting Engineering” (edited by the Institute of Electrical Engineers of Japan, published by Ohmsha, p. 36).

 The reason why the color rendering properties are evaluated based on the light of the perfect radiator is that natural light (sunlight) is close to that of the perfect-radiator. The light emitted by the perfect radiator includes light of each wavelength continuously. Since the color of the object is determined by the light reflectance (spectral reflectance) for each wavelength of the object, the light of each wavelength is continuously included in the spectral distribution of the illumination light (luminous body), and However, if the intensity distribution is close to that of a perfect radiator, the color appearance of the object will be similar to that under natural light. However, even if the LED white light emitter composed of RGB emits white light as a whole by adjusting the intensity ratio of each color, its spectral distribution is not continuous, and R (red), G ( It is discontinuous with narrow peaks only at three wavelengths, green (green) and B (blue). Because of this discontinuity, RGB-LED emitters cannot have sufficient color rendering properties as lighting devices.

 As a light source for white illumination using a single LED, a gallium nitride blue LED covered (or coated) with a YAG phosphor has been devised (see Japanese Patent Application Laid-Open No. 5-152609). This is because the YAG phosphor is photo-excited using blue light (wavelength 46 Onm) from the InGaN active layer of a gallium nitride blue LED, and the color mixture of the yellow light, which is the fluorescence from the phosphor, and the blue light from the LED. To obtain white light.

Fig. 1 shows a spectrum of a white LED (correlated color temperature: 6500K) consisting of a gallium nitride blue LED coated with a YAG phosphor and a spectrum of standard light Ik (correlated color temperature: 6504K). . Here, the standard light ^ is a standard light for color rendering evaluation representative of daylight having a color temperature of 6504K, and is determined by the CIE through statistical processing of measured values of the natural daylight spectral distribution. As for the spectral distribution of the white LED, the spectral distribution in the purple to blue-violet region, the blue-green to green region, and the red region is lower than that of the color rendering standard light D ^. Fig. 2 shows the color rendering index of the white LED. It can be seen that the special color rendering indexes of blue-violet, green and red are inferior to the spectral distribution. Therefore, depending on the field of application It is necessary to reinforce the spectral component in some way to enhance the color rendering of the object.

 As an example, we will discuss the medical application field. On September 11, 2000, the world's first surgical operation using a white LED lighting device (internal shunting for a patient with chronic renal failure) was successfully performed at the Kyoto Prefectural Yosei Hospital. This illuminating device is made by arranging white LED chips made of a gallium nitride blue LED coated with a YAG fluorescent material in an array to form a light emitting panel, and mounting this on plastic goggles. This operation was performed with sufficient illuminance under one-battery operation, demonstrating the usefulness of white LEDs as a handy lighting device that surgeons can wear.

 However, it was pointed out that, during the above-mentioned operation, it was difficult to distinguish between the color rendering properties of the white LED, for example, arteries (clear red) and veins (dark red) of the veins (dark red). This is because there is a problem in the color rendering properties of the used white LED in the red region, and it is solved by increasing the spectrum of the red region of 597 to 640 nm or reddish region of 640 to 780 nm. It is thought that it can be done.

 As a means for strengthening the spectrum in the red region, it is conceivable to first distribute an AlGalnP-based LED or an AlGaAs-based LED on a plane in a white LED chip vertically and horizontally. However, in order to mix the emission spectra evenly in the radiation plane, it is necessary to distribute the chips as densely and evenly as possible, or to mount a diffusion plate on the surface of the LED light emitting panel. Moreover, the intensity of the white LED (YAG phosphor coated—gallium nitride blue LED) and red LED (AlGalnP LED or AlGaAs LED) must be controlled independently. The easiest way to increase the spectrum in the red region without causing the above problems is to apply a phosphor emitting in the red region to a current white LED. However, in the case of lighting equipment widely used in general, it is essential that the red phosphor has high efficiency but high stability. In addition, it is also an important requirement that it has high processability, does not contain components that are toxic to the human body, and does not contain substances that, if discarded, would pollute the global environment.

Although high luminous efficiency can be obtained by using an organic molecular material such as mono-damine as a phosphor in the red region, it is not suitable for practical use because it is easily decomposed and quenched by light irradiation. ZnCdS: Ag-based and Y ₂ 0 ₂ S: Eu phosphor is used as a cathode ray tube red phosphor television (electron beam excitation), a relatively high red conversion in ultraviolet region of the LED light source (360～380Nm) can get. However, blue excitation does not provide sufficient conversion efficiency, so it cannot be combined with currently used white LEDs (YAG phosphor-coated gallium nitride blue LEDs). Considering that the luminous efficiency of the current ultraviolet LED is much lower than that of the blue LED, this is not a practical combination either. In addition, these phosphors can achieve long-term stability only in a cathode ray tube that has been sealed off in a vacuum. In the air environment, moisture absorption occurs, photochemical reactions are accelerated, and phosphor degradation occurs. Problems arise. A sealing technique for solving this has not yet been developed. In addition, the ZnC dS: Ag system contains Cd, and its effects on the environment are concerned.

 Considering this, regarding the red phosphor that can be combined with the current white LED, the phosphor that has been developed so far has various problems.

 Conventionally, various fluorescent materials have been developed by adding rare earth metals such as Eu (europium), Tb (terbium) and Tm (thulium) to substances such as inorganic oxides and inorganic sulfides. However, the energy gap theory of quantum physics has traditionally stated that "rare earth metals do not easily emit light in organic media." In fact, until recently, the luminous efficiency of rare earth metals in organic media such as plastics has been extremely low. It was low.

 In contrast, some of the inventors of the present invention have begun to reexamine the energy gap theory, and in 1995 the world's first design of a group of complexes of rare earth metals such as neodymium, which can emit light in organic media. Succeeded (Yasuya Hasegawa, "How to shine a neodymium that does not shine in organic media?", Chemistry and Industry, Vol. 53 (2000) No. 2, p. 126-130). A patent application was also filed for some of these (PCT / JP98 / 0097OW098 / 40388, Japanese Patent Application No. 10-238973 = Japanese Patent Application Laid-Open No. 2000-63682, Japanese Patent Application No. 11-62298 = Japanese Patent Application No. 2000-256251. Gazette). These complexes are stable even at a high temperature of 350 ° C, and are unlikely to undergo photodegradation, and break the conventional wisdom that organic compounds tend to be degraded by heat or light irradiation. In addition, it has high affinity with resin-based host materials such as plastics and polymers, and is expected to be a next-generation optical device in combination with easy processability.

The present invention first uses and selects a substance suitable for the purpose among these complexes in order to realize the white LED having a high color rendering property, and uses a light emitting diode or a semiconductor having an InGaN-based light emitting layer. The laser may be used as an organometallic complex of a rare earth ion, a nano-sized host-guest complex containing these metal complexes, or a metal complex or a metal complex thereof. Has realized a white LED for high color rendering illumination by covering it with a transparent polymer containing a complex.

 However, the range of the present invention does not stop there. The present inventors have paid attention to the fact that the wavelength range of the excitation light of the rare-earth complex is extremely narrow, so that it can be a highly efficient wavelength-converted light-emitting device. In other words, by combining the rare earth complex with a light emitting diode having a relatively narrow emission wavelength range or a semiconductor laser having a similarly narrow emission wavelength width, a light emitting device having very high efficiency and high brightness as a whole is obtained. I thought that it could be used as In addition, light-emitting diodes or semiconductor lasers are very small, and rare-earth complexes have good affinity for plastics and polymers, so they have a wide range of practical applications as small, lightweight, and long-lasting light-emitting devices. He decided to bring the present invention to the world. Disclosure of the invention

 Therefore, the basic configuration of the light emitting device according to the present invention corresponds to the transparent solid support containing one or more of the rare earth complex groups having the following structural formula, and the f_f transition of the central ion of the complex. And a light emitting diode or a semiconductor laser that emits excitation light.

General formula (I)

(In this formula, M represents a rare earth atom, nl represents 2 or 3. N2 is 2, 3 or represents a 4. Rf 'and Rf ² are free of the same or different and each represents a hydrogen atom C, ~ (^ Represents an aliphatic group, an aromatic group containing no hydrogen atom, or a heterocyclic group containing no hydrogen atom; ϊ and X ² are the same or different and represent a group IVA atom, a VA group atom excluding nitrogen, and oxygen Group VIA atoms excluding And n3 and n4 each represent 0 or 1. Y represents C—Ζ ′ (Ζ ′ represents a deuterium, a nitrogen atom or a hydrogen atom-containing ₂ or less aliphatic group), N, P, As, Sb or Bi. However, when X ¹ is a carbon atom, n3 is 0, and when X ² is a carbon atom, n4 is 0.When X ¹ and X ² are both carbon atoms, at least one of Rf and Rf ² is hydrogen It is an aromatic group containing no atoms. )

General formula (II)

(In this formula, M, nl and n2 are as defined above. Rf ³ is free of aromatic group or a hydrogen atom does not contain an aliphatic group Ci～C ₂₂ containing no hydrogen atom, the hydrogen atom X ³ represents any one of a group IVA atom excluding carbon, a group VA atom excluding nitrogen, and a group VIA atom excluding oxygen, and n5 represents 0 or 1.)

General formula (I I I)

(In this formula, M, Rf ¹ , Rf ² , nl and n2 are as defined above.) General formula (IV)

(In this formula, M, Rf, Rf ² , nl and n2 are as defined above.)-General formula (V)

(In this formula, M, Rf ¹ , Rf ² , nl, n2 and Z ′ are as defined above,

)

General formula (VI)

(In this formula, M, nl and n2 are as defined above. Z ′ ″ represents a hydrogen atom or Ζ ′ (Ζ ′ is the same as above.) Rf ⁴ and Rf ⁵ are the same or Differently containing no hydrogen atom ^ ~ (^ aliphatic group, hydrogen atom-free aromatic group or hydrogen atom A heterocyclic group. )

Specific examples of the above-mentioned hydrogen atom-free to ( ₂₂ aliphatic groups, hydrogen-free aromatic groups, hydrogen-free heterocyclic groups, and X ¹ , X ² , and X ³ are described in It is described in [0031] to [0037] of 2000-63682, so please refer to that, and the synthesis method of the above complex is also described in [0047] to [0067] of the same publication. .

 Among these rare-earth complexes, those having Rfl and Rf2 of up to about C1 or C2 are favorable in terms of affinity with the later-described transparent solid carrier plastic-polymer, and among them, particularly CF3 or CF2CF3 produces stable polymers.

The light emitter to excite the rare earth complex, ^3, the nitride semiconductor light emitting diode or a semiconductor laser using the same having a light emission layer of the general formula IihGanN OKx rather 1). By changing the component variable X, excitation light of ff transition of various rare earth ions can be arbitrarily generated, and highly efficient excitation of the center ion of the rare earth complex can be performed.

 The most commonly used transparent solid carriers are transparent resins. Since the resin is very lightweight and has excellent workability, the application range of the light emitting device according to the present invention is very wide. As the transparent resin, a polymer matrix described in [0069] of JP-A-2000-63682 can be used. A method for dispersing the above Eu complex in a transparent resin is described in [0070] of the publication.

 As the transparent solid carrier, the rare-earth complex is not directly mixed into the transparent resin as described above, but once supported on a (host-guest) composite having an average particle size of nano- One guest) A complex in which a complex is mixed in a transparent resin, or a liquid containing the complex in a transparent container can also be used. The type and manufacturing method of the nano-sized (host-guest) complex supporting the rare earth complex are described in detail in JP-A-2000-256251.

 The rare earth complex is an organic complex containing the above-mentioned various ligands with a divalent, trivalent or tetravalent ion of a rare earth element as a central ion. In the present invention, the central ion emits light to be described later. By doing so, it functions as an optical material.

Rare earth elements are scandium Sc (atomic number 21), yttrium Y (atomic number 39) and lanthanoids (atomic numbers 57 to 71: lanthanum La, cerium Ce, It is a collective term for the 17 elements: raceodymium Pr, neodymium Nd, promethium, samarium Sm, europium Eu, gadolinium Gd, terbium, dysprosium! ^, Holmium Ho, erbium Er, thulium Tm, ytterbium Yb, lutetium. Rare earth elements are generally stable in compounds with an oxidation number of 3, but some of them are tetravalent in Ce and divalent in Sm, Eu, and Yb. In terms of atomic structure, the two elements before Sc and Y are the main transition elements that fill the 3d shell, and the 15 lanthanides are the inner transition elements that fill the 4f shell. Lanthanides have a ground electron configuration of (n_ 2) f ° ^M4 (n-l) s ² (n- l) p ⁶ (n- l) d ° ~ ¾s ² (where n is 6 or 7).

 Rare earth elements are known to form many complexes, but in the complex, the energy level of the transition shell of the rare earth element is split, resulting in various energy levels. By appropriately selecting the rare earth element and its surrounding ligands, we see that the transition between the energy levels in the 4f shell (ff transition) can be a useful optical material in practical use. That is the above-mentioned prior application.

 The present invention teaches the excitation means and further clarifies its specific application in order to further promote its practical use. That is, the rare earth complex optical material was regarded as a wavelength conversion element, and a light emitting diode or a semiconductor laser was used as the input. Then, the rare earth complex was supported on a transparent solid medium (carrier) so that it could be used as a specific optical element or optical component.

 Light emitting diodes have a relatively narrow emission wavelength range. On the other hand, the excitation range of the rare-earth complex is extremely narrow (lnm or less) because the excitation is exclusively due to the trif transition of the specific ion of the complex ion which is the central ion. Therefore, by adjusting the emission wavelength of the light emitting diode to the excitation wavelength of the complex, the energy of the light emitting diode can be efficiently used for exciting the complex, the wavelength can be converted, and the light can be emitted as light of a longer wavelength. Here, since the emission wavelength range of the light emitting diode is not as narrow as the excitation wavelength range of the rare earth complex, part of the light of the light emitting diode is not used for excitation. Therefore, in the light emitting device according to the present invention, which is a combination of the light emitting diode and the rare earth complex substance (carrier), the light emitted from the light emitting diode and the mixed light of the rare earth complex are emitted.

It is another object of the present invention to utilize this in the above-described high color rendering white LED, and in that case, europium (Eu) is used as a rare earth element. When using Eu The structural formulas of the above complexes are as follows. Structural formula (le)

Structural formula a I e)

Structural formula (I lie)

Structural formula (IVe)

構造式 (Ve)

Structural formula (Ve)

構造式 (Vie)

Structural formula (Vie)

(Rfl, Rf2, etc. in the above structural formula are the same as those described in the above general formulas (I) to (VI).)

Eu is an element belonging to the lanthanoid with atomic number 63, and its trivalent ion Eu ³⁺ can increase the ff transition excitation energy at wavelengths around 394, 420, and 465 nm (all blue) by properly designing the ligand. In addition, the radiant energy can be set to a wavelength around 600 to 700 nm (red light). Of these, excitation at a wavelength of 394 nm has particularly high luminous efficiency. When a specific wavelength value (for example, “394 nm”) is mentioned in this specification (including claims), there must be a width corresponding to the physical property or measurement technique before and after that value. Is natural. For example, when the wavelength refers to the wavelength of the excitation light of the rare-earth complex, the width is narrow, not more than lnm, regardless of the type of ligand physicochemically. It includes the width of the degree. In addition, the wavelength of the fluorescence emission may include a large number of transitions between levels due to physicochemical factors, and thus the width may be as large as 10 nm or more.

On the other hand, a nitride semiconductor LED or a semiconductor laser represented by the general formula In _x Ga _{x x} N (0 <x × 1) can control light of any wavelength in the blue to ultraviolet region by controlling its component variable X. It can be emitted, but when the Eu complex is used as the rare earth complex, the component variable X for generating the excitation light at wavelengths around 394, 420, and 465 nm is about 0.1 to 0.5. .

 By combining these two, the mixed light of the light-emitting diode with the blue + Eu complex and the red light of the light-emitting diode and the yellow + Eu complex of the light-emitting diode + Eu complex are further combined by combining the Y phosphor. A mixed light is obtained.

As an example, the emission spectrum and the excitation spectrum of the Eu (pms) ₃ complex (pms-perfluorophenylmethane) having the above structural formula (IVe) (where Rfl = Rf2 = CF ₃ , n2 = 3) Are shown in FIGS. 3 and 4. As shown in FIG. 3, the emission spectrum is formed from three bands of 599.8 nm, 611.6 nm and 697 nm. Since the relative intensity ratio between these emission bands can be changed depending on the host material of the metal complex, it is possible to control the color tone from orange to red. On the other hand, the excitation spectrum in FIG. 4 is composed of the band of the Eu ff transition absorption. Since these ff transitions directly photoexcitate Eu ³⁺ , there is no problem of degradation due to actual carrier excitation of ligands and host materials. In particular, the excitation peak at 394 mn is a sharp and strong band. For this reason, a combination with a light emitting diode is also effective, but wavelength conversion is particularly effectively performed by using an InGaN-based semiconductor laser having a narrow emission half width. Currently, the InGaN-based laser diode is a device with an optical output of 2 (W) in the 390-410 nm band, and a high output characteristic of 400 mW or more has been reported at the laboratory level. Therefore, it emits at 394 nm. The combination of a high-power semiconductor laser and an Eu ³⁺ complex can achieve ultra-bright red light emission.This device is not only effective as an illumination device, but also a laser-excited diode. High impact as spray application.

 On the other hand, the absorption band in the 340 to 360 nm, 370 to 385 nm, or 460 to 475 nm region, or the background absorption in other wavelength regions is relatively broad, so that the combination with the light emitting diode is also effective. In particular, the absorption band in the 460 to 475 nm region almost matches the current InGaN blue emission band of white LEDs, so the Eu concentration is adjusted appropriately to produce a red phosphor and applied to the white LED. Then, a part of the blue light is converted to red fluorescence, and a white light emission spectrum with a slightly lower color temperature and improved color rendering in the red region can be realized.

The emission wavelength range of Eu ³⁺ was orange to red, but by arranging another rare earth element ion at the central ion M of the rare earth complex represented by the general formulas (I) to (VI), Light emission of various colors can be obtained. For example, Tb ³⁺ emits green light (excitation wavelengths 304 and 280 nm; emission wavelengths 490, 543, 580 and 620 nm), and Eu "and Ce ³⁺ emit blue light. By exciting the LED with a suitable LED, a light emitting device of each color can be manufactured.

White LED (correlated color temperature: 6500K) comprising a first drawing YAG phosphor coated with nitride Gariumu based blue LED and scan Bae spectrum of a standard light D ₆₅ (correlated color temperature: 6504 K) scan Bae spectrum Dara off of.

 Fig. 2 Table of color rendering index of white LEDs and other white light sources.

FIG. 3 is a graph of the emission spectrum of the Eu (pins) ₃ complex.

FIG. 4 is a graph of the excitation spectrum of the Eu (pms) ₃ complex.

Fig. 5 A graph showing the results of measuring the spectrum of transmitted light by covering an InGaN blue LED with a central emission wavelength of 394M1 with poly (methyl methacrylate) carrying a Eu (pms) ₃ complex.

Fig. 6 Graph showing the results of measuring the spectrum of transmitted light by covering an InGaN blue LED with a central emission wavelength of 465MI over a methyl methacrylate (PMMA) supporting Eu (pms) ₃ complex.

Fig. 7 Eu (puis) ₃ complex is overlaid on a white LED in which an InGaN blue LED is covered with a YAG phosphor. 5 is a graph showing the result of measuring the spectrum of the transmitted light.

 FIG. 8 shows a light emitting device in which a blue InGaN-LED and a YAG phosphor are sealed in a plastic case containing an Eu complex, which is one embodiment of the present invention.

 FIG. 9 is a schematic configuration diagram of an automobile brake lamp including a semiconductor laser and a Eu complex-containing plastic cover, which is another embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Fig. 5 shows the measurement of the spectrum of the transmitted light of polymethyl methacrylate (PMMA) carrying the above Eu (pms) ₃ complex over InGaN purple LED. The InGaN-LED is obtained by adjusting the component variable X so that the center of the emission wavelength is 394 nm.As intended, the LED has a relatively narrow emission peak in the range of 390 to 410 nm. , A sharp absorption peak due to the Eu complex occurs. In addition, a large emission peak due to the Eu complex appears at 611 nm, and a small emission peak appears near 591 nm. When this excitation light is used, a high luminous efficiency of about 50 to 70% can be obtained.

 FIG. 6 shows the result of the same measurement performed by adjusting the component variable X of the InGaN-LED so as to cover 465 nm, which is another excitation light of the Eu complex. Similarly, among the LED emission peaks, a steep absorption peak of 465 nm due to the Eu complex occurs, and the emission peak appears near 611 M1, but the emission efficiency due to this excitation wavelength is not so large. As a result, the peak at 591 nm hardly appears.

Fig. 7 shows the results of the same measurement performed by covering the above-mentioned Eu complex on a conventional white LED (an InGaN blue LED covered with a YAG phosphor). At 465 nm, the absorption peak due to the Eu complex is clearly observed. As a result, a slightly smaller emission peak appears near 615 M1. As is evident from this figure, the light-emitting device fabricated in this way is close to the ideal white color that supplements the red component missing in the conventional white LED, and the light source using it has a very high color rendering. It becomes a white light source with high performance. It can be used as a useful light source in fields where color discrimination or color rendering is particularly required, such as surgery and product displays. That is, the light emitting device according to the present invention is used in the field of medical lighting, the field of lighting in museums and restaurants, and In the field of indoor lighting.

 As a specific shape of this light emitting device, as shown in FIG. 8, it is preferable to have the same shape as a conventional bullet-shaped white LED light emitting device. The conventional bullet-shaped white LED light-emitting device is a device in which the InGaN-LED 81 is covered with a YAG phosphor 82 and sealed in a bullet-shaped epoxy resin package 83. However, it also plays the role of a lens that collects light emitted from the LED (through the YAG phosphor). By mixing the Eu complex in the package resin 83, a light emitting device 80 as one embodiment of the present invention is obtained. In this way, by adopting the same shape as before, the white LED light emitting device conventionally used in various places can be replaced with the light emitting device according to the present invention as it is, and there is a great economic effect of inheriting assets. be able to.

 Next, a light emitting device having characteristics different from those described above can be obtained by combining the rare earth complex with a semiconductor laser. Semiconductor lasers have extremely narrow emission wavelengths. Therefore, by matching the emission wavelength with the excitation wavelength of the rare-earth complex, it is possible to obtain a light-emitting device that converts all the light of the semiconductor laser into light of another wavelength and emits only the light of the rare-earth complex.

 The features of this light emitting device are that the rare earth complex can be supported on various resins and the like, and that the excitation means is a light and compact semiconductor laser. This opens up a wide range of practical applications. As an example, it can be used for a car brake lamp.

As shown in Fig. 9, a plastic cover 91 (also referred to as a lens) carrying the rare-earth complex is provided at the rear (in the case of a brake lamp) of the car 90, and the same wavelength as the excitation light is emitted behind it. Semiconductor laser 92 to be disposed. Then, when the brake 93 is not depressed, the appearance of plastic such as transparent or white is exhibited. When the brake 93 is depressed, the semiconductor laser 92 emits light, the wavelength is converted by the plastic cover 91, and the color is red. Light will be emitted backward from the car 90. In addition, a diffusion plate (diffuser) 94 for diffusing the laser light is provided in front of the semiconductor laser 92. More compact brake lamps are also conceivable. As shown in FIG. 9 (c), the periphery of the flat plastic cover 95 carrying the rare-earth complex is surrounded by a reflective wall 96, and the semiconductor laser 97 is mounted at one place around the same. Light to plastic power It should be fired obliquely in a par 95 flat plate. By doing so, the laser light is repeatedly reflected by the surrounding reflective wall 96, and while passing through the plastic cover 95, the wavelength is converted by the rare earth complex carried there, and the red light (other light) is emitted. When a rare earth element is used, light of a unique color such as blue or green) is emitted from the surface of the plastic cover 95. In addition, when light is emitted only to the rear like a brake light of a car, it is desirable to provide a reflector on the other surface.However, when used as an indicator for doors, etc., light is emitted from both surfaces. It may be released.

 The application example of the light emitting device according to the present invention has been described above, but the application example is not limited to the above. For example, it can be used for a decorative panel installed in a store or the like, a backlight or a sidelight for a liquid crystal display device such as a personal computer, a portable terminal, and a mobile phone. Various other applications are possible within the spirit and scope of the present invention.

Claims

The scope of the claims 1. A transparent solid support containing one or more of the rare earth complexes having the following structural formula, and a light emitting diode or a semiconductor laser emitting excitation light corresponding to the ff transition of the central ion of the complex. A light emitting device characterized by being combined. General formula (I)

(In this formula, M represents a rare earth atom, nl represents 2 or 3. N2 is 2, 3 or represents a 4. Rf 'and Rf ² are free of the same or different and each represents a hydrogen atom C, ~ C _{22 represents} an aliphatic group, an aromatic group containing no hydrogen atom, or a heterocyclic group containing no hydrogen atom; Γ and Γ are the same or different and represent a group IVA atom, a group VA atom excluding nitrogen, and oxygen Excluding any of the VIA group atoms, and n3 and n4 represent 0 or 1. Υ represents C-1 ′ ′ (Ζ ′ does not include deuterium, octogen, or hydrogen (^ ~ (: ₂₂ Represents an aliphatic group of), N, P, As, Sb or Bi, provided that when X ¹ is a carbon atom, n3 is 0, and when X ² is a carbon atom, n4 is 0, and X ¹ And when X ² is simultaneously a carbon atom, at least one of Rr and Rf ^z is an aromatic group containing no hydrogen atom.) General formula (II)

(In this formula, M, nl and n2 are as defined above. Rf ³ is a hydrogen atom-free C, ~ (^ aliphatic group, a hydrogen atom-free aromatic group or a hydrogen atom. There heterocyclic group indicates to an included; X ³ is, IVA group atoms excluding carbon, VA group atoms excluding nitrogen, can n5 represents any group VIA atom other than oxygen represents 0 or 1).. General formula (I I I)

(In this formula, M, Rf Rf \ nl and n2 are as defined above.)-General formula (IV)

(In this formula, M, Rf ¹ , M nl and η 2 are as defined above.) General formula (V)

(In this ^{formula, M, Rf, Rf 2,} nl, n2 and Z 'are as defined above, ) General formula (VI)

(In this formula, M, nl and n2 are as defined above. Z ′ ″ represents a hydrogen atom or Ζ ′ (Ζ ′ is the same as above.) Rf ⁴ and Rf ⁵ are the same or Differently containing no hydrogen atom (shows an aliphatic group of, to ^, an aromatic group containing no hydrogen atom, or a heterocyclic group containing no hydrogen atom.) 2. The light emitting device according to claim 1, wherein the central ion is Eu ³⁺ . 3. The light emitting device of claim 1, wherein the central ion is characterized in that it is a Tb ³ 4. The light emitting device according to claim 1, wherein the central ion is Eu ²⁺ . 5. The light emitting device according to claim 1, wherein the central ion is Ce ³⁺ . 6. The light-emitting diode or the semiconductor laser has a light-emitting layer represented by a general formula In _x G _{ai -x} N (0 <x <l). Light emitting device.  7. The method according to claim 2, wherein an excitation wavelength of the rare earth complex is 394 nm, and an emission wavelength spectrum of the light emitting diode or the semiconductor laser has a peak at approximately 394 nm. Light emitting device.  8. The light emitting device according to any one of claims 2 to 7, wherein a YAG phosphor is combined in addition to the above.  9. The light emitting device according to any one of claims 1 to 8, wherein the transparent solid carrier is a transparent resin.  10. The light emitting device according to any one of claims 1 to 9, wherein the transparent solid support includes a (host-guest) complex having an average particle size of nanometers, which carries the complex.  11. The lighting device according to any one of claims 1 to 10, wherein the light-emitting diodes are arranged vertically and horizontally on a plane.  12. An automobile brake lamp using the light emitting device according to any one of claims 1 to 10.  13. A decorative panel using the light-emitting device according to any one of claims 1 to 10.  1 4. A liquid crystal display device, wherein the light emitting device according to any one of claims 1 to 10 is used as a backlight or a side light.